You start as a car driving along a 2d isometric side scrolling road. I think you destroy or dodge othe cars.
But then you reach water and turn into a speedboat.
Then randomly a jet.
Sorry there aren't more details... I have been looking for this game for a better part of a decade and just had zero luck
If it helps. There was a game that released called "Agent Intercept" this year that is almost identical to to old game.